Hi folks

Last year through rushing around before my trip to france, i retimed my motor very inaccurately and consequently burnt what had been up to then a perfect & original BSA valve, it got me over & back but was far from perfect on the trip

I replaced it since then but am loathe to bin it,

Question is - could the valve face be recut on a lathe ? It had only done about 3000 miles and appears only to have got hot in 2 areas

If so, can any one be recommended to do the job

Best regards

Jo'b

email (option): Jonnyob1@googlemail.com

When the damage is not to big I would clean it up, I have done it a few times already and have been using these valves for a long time.

Henk

email (option): ahum@quicknet.nl

Hi John..You need to find an engine shop that has a valve resurfacer...These grind the valve face to an accurate angle....The thing you need to look at is how much the 'land' above the valve seat will be ground away during the clean up. If the land is reduced too far it will probably fail again fairly rapidly as the edge of the valve will overheat if it is too thin..Ian.

email (option): ian@wright52.plus.com

The yellow pages in Slough so

:-D

Thanks folks

Jo'b

email (option): Jonnyob1@googlemail.com

I have a valve refacer if thats any use

email (option): davmax@ntlworld.com

You can also reface the valve with hard facing and get it reground but the cost is usually greater than replacig the old one.
OTOH it could be reground down to a size good for a 350 and be the beginning of a new bike project.

email (option): wariron@tpg.com.au

Hi Trevor...I asked a guy with a lot of NOS valves at a jumble if he had any M20 valves...He replied he had just sold a bunch of them to a guy who wanted them as donors for another bike..New M20 valves!!!...Grrrr ...Ian

email (option): ian@wright52.plus.com

Well I am not supprised.
You do not usually start making a bobber/chopper with a Brough Superior
So if you are going to do some thing "special" you looks for cheap parts and very few are cheaper than M20 ones.

email (option): wariron@tpg.com.au

The long stem and large head diameter help as well..The stem can be shortened for an OHV motor and simply have the collet grooves remachined in the desired position and likewise, the head sizes will do most engines with a simple modification...One drawback though is that you get the M20s 'bastard size' valve stems, which makes it awkward to size the valve guides correctly unless you have the correct tooling...Personally, I hope that bloke who bought 'my' valves struggled.. ....Ian

email (option): ian@wright52.plus.com

Hi all

Thanks for the feedback

Will look for someone local - if that fails in the bin - a shame as its an original BSA item

Job

email (option): Jonnyob1@googlemail.com

Now there's a lesson for everyone in the importance of having the ignition timing set correctly...Ian

email (option): ian@wright52.plus.com